Bacteria, Beneficial: Brevibacterium linens, Brevibacterium aurantiacum and Other Smear Microorganisms

Abstract

Smear or washed-rind cheeses develop an orange to red color on their surfaces during ripening, which is composed of bacteria and yeasts. For a long time, it was considered that Brevibacterium linens was the only major bacterium on the surfaces of these cheeses. This organism was recently shown to be a mixture of two species, B. linens and the new species, Brevibacterium aurantiacum. Both organisms produce pale yellow to deep orange or brown colonies, which are responsible for the orange to red color of the cheese. Several other new species of bacteria have recently been found on the surface of smear-ripened cheese, including Arthrobacter arilaitensis and Arthrobacter bergerei, which were originally isolated from Reblochon and Camembert cheese, respectively, Staphylococcus succinus subsp. casei and Staphylococcus equorum subsp. linens, which were isolated from a Swiss smear cheese made from raw milk, Agrococcus casei, Corynebacterium casei, and Microbacterium gubbeenense, which were initially isolated from Gubbeen cheese, and Mycetola reblochonii, which was isolated from Reblochon. Their sources and their role in cheese ripening are described.